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Related papers: A symplectic approach to gravitational instability

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We present a new approach to the problem of proving global stability, based on symplectic geometry and with a focus on systems with several conserved quantities. We also provide a proof of instability for integrable systems whose momentum…

Mathematical Physics · Physics 2025-10-28 Verónica Errasti Díez , Jordi Gaset Rifà , Manuel Lainz

We show that the formation of large-scale structures through gravitational instability in the expanding universe can be fully described through a path-integral formalism. We derive the action S[f] which gives the statistical weight…

Astrophysics · Physics 2009-11-10 P. Valageas

The purpose of this paper is to study the relations between different concepts of dispersive solution for the Vlasov-Poisson system in the gravitational case. Moreover we give necessary conditions for the existence of partially and totally…

Mathematical Physics · Physics 2012-05-31 Simone Calogero , Juan Calvo , Óscar Sánchez , Juan Soler

Classical gravitation is treated from the point of view of non-equilibrium thermodynamics. Gravitational potential is a thermodynamic state variable in a weakly nonlocal treatment. Entropy production is calculated and the simplest solution…

Statistical Mechanics · Physics 2019-05-28 P. Ván , S. Abe

The gravitational instability of inhomogeneities in the expanding universe is studied by the relativistic second-order approximation. Using the tetrad formalism we consider irrotational dust universes and get equations very similar to those…

Astrophysics · Physics 2009-10-28 H. Russ , M. Morita , M. Kasai , G. Boerner

One of the challenges when simulating astrophysical flows with self-gravity is to compute the gravitational forces. In contrast to the hyperbolic hydrodynamic equations, the gravity field is described by an elliptic Poisson equation. We…

Numerical Analysis · Mathematics 2021-06-30 Michael Schlottke-Lakemper , Andrew R. Winters , Hendrik Ranocha , Gregor J. Gassner

The kinetic approach to the formation of the filaments in the large-scale matter distribution in the Universe is considered within the Vlasov formalism. The structures arise due to the self-consistent dynamics, along with the repulsive term…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 V. G. Gurzadyan , N. N. Fimin , V. M. Chechetkin

We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. Starting from the perturbed Einstein equations, we integrate out the non-relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ram Brustein , Antonio Riotto

This paper introduces a global uncertainty propagation scheme for rigid body dynamics, through a combination of numerical parametric uncertainty techniques, noncommutative harmonic analysis, and geometric numerical integration. This method…

Dynamical Systems · Mathematics 2008-03-12 Taeyoung Lee , Melvin Leok , N. Harris McClamroch

The general solution of the gravitational field equations for a full causal bulk viscous stiff cosmological fluid, with bulk viscosity coefficient proportional to the energy density to the power 1/4, is obtained in the flat…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. K. Mak , T. Harko

We discuss several approaches to generalized solutions of problems describing the motion of inviscid fluids. We propose a new concept of dissipative solution to the compressible Euler system based on a careful analysis of possible…

Analysis of PDEs · Mathematics 2019-07-04 Dominic Breit , Eduard Feireisl , Martina Hofmanova

As is well known from the work of R. Glassey} and J. Schaeffer, the main energy estimates which are used in global existence results for the gravitational Vlasov-Poisson system do not apply to the relativistic version of this system, and…

Mathematical Physics · Physics 2007-12-03 Mahir Hadzic , Gerhard Rein

This paper reviews the essential physics of gravitational instability in a Robertson-Walker background spacetime. Three approaches are presented in a pedagogical manner, based on (1) the Eulerian fluid equations, (2) the Lagrangian…

Astrophysics · Physics 2007-05-23 Edmund Bertschinger

Using recent developments in the theory of globally defined expanding compressible gases, we construct a class of global-in-time solutions to the compressible 3-D Euler-Poisson system without any symmetry assumptions in both the…

Analysis of PDEs · Mathematics 2017-12-04 Mahir Hadzic , Juhi Jang

This paper is devoted to analyze the dynamical instability of a self-gravitating object undergoes to collapse process. We take the framework of generalized teleparallel gravity with cylindrically symmetric gravitating object. The matter…

General Relativity and Quantum Cosmology · Physics 2016-10-31 Abdul Jawad , Davood Momeni , Shamaila Rani , Ratbay Myrzakulov

We consider cosmological solutions to general relativity with a single barotropic fluid, where the pressure is a general function of the density, $p = f(\rho)$. We derive conditions for static and oscillating solutions and provide examples,…

High Energy Physics - Theory · Physics 2015-12-31 John Kehayias , Robert J. Scherrer

We show how to systematically apply the Faddeev-Jackiw symplectic method to General Relativity (GR) and to GR extensions. This provides a new coherent frame for Hamiltonian analyses of gravitational theories. The emphasis is on the…

General Relativity and Quantum Cosmology · Physics 2020-05-14 Davi C. Rodrigues , Mariniel Galvão , Nelson Pinto-Neto

The Nordstr\"om-Vlasov system is a relativistic Lorentz invariant generalization of the Vlasov-Poisson system in the gravitational case. The asymptotic behavior of solutions and the non-linear stability of steady states are investigated. It…

Mathematical Physics · Physics 2009-11-13 Simone Calogero , Oscar Sanchez , Juan Soler

This article studies the N-vortex problem in the plane with positive vorticities. After an investigation of some properties for normalised relative equilibria of the system, we use symplectic capacity theory to show that, there exist…

Dynamical Systems · Mathematics 2018-09-26 Qun Wang

In this paper we study the kinetic theory of many-particle astrophysical systems imposing axial symmetry and extending our previous analysis in Phys. Rev. D 83, 123007 (2011). Starting from a Newtonian model describing a collisionless…

General Relativity and Quantum Cosmology · Physics 2012-08-23 J. Ramos-Caro , C. A. Agón , J. F. Pedraza
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